which headphone performs outstanding in all genres under 300 aus dollars budget?

esp ambient music like cafe del mar? beethoven?

i have been reading every possible review here and am not able to conclude anything.

too many choices i guess.

If you don't care about its only "medium" level of isolation, this one is easy IMO...the Kef M500s. The most neutral headphones I've tested here and work so well with every music genre I've thrown at them.

Actually using speaker compensation isn't totally the right thing after talking with Tyll. Due to the speakers on headphones being right next to your ears and no crossfeed information (right ear can't hear the left driver and visa versa) headphones require their own methodology.